The present subject matter relates generally to a method for the removal of oxygen from hydrogen using a manganese, iron, nickel or cobalt based adsorbent. More specifically, the present subject matter relates to the methods for the removal of oxygen from hydrogen using a manganese based adsorbent without the generation of water or other oxides.
Hydrocarbons and hydrogen used in industry should be as pure as possible without the presence of contaminants. Conventionally, oxygen is a contaminant in hydrogen and some hydrocarbon feedstocks. The purification of hydrogen is needed for many refining and petrochemical applications. There have been several absorption systems proposed and used for removal of oxygen from gas mixtures, but each is characterized by important limitations. For example, certain systems require elevated temperatures for effective removal and this requires additional heating equipment if the feed gas is available at ambient temperature. Another disadvantage of conventionally known oxygen removal systems is their inability to provide an oxygen free product without addition of other impurities during this removal. Certain end uses of the hydrogen gas require complete removal of trace amounts of oxygen without simultaneous introduction of other impurities.
The previously employed oxygen adsorbents for removal of oxygen from hydrogen and hydrocarbons have a tendency to pulverize easily and cause powder carryover from the adsorbent chamber into the product gas system. Besides the contamination problem, attrition of the adsorbent reduces the overall efficiency. Therefore, there is a need to remove oxygen contaminants from hydrogen gas completely to meet the product gas specifications for commercial use.
Typically, the copper based adsorbents used to remove oxygen from the feeds will often lead to water generation as the copper oxides react with hydrogen to form elemental copper and water. Copper oxides are particularly susceptible to reduction especially by hydrogen at lower temperatures depending on the partial pressure. This reaction of copper oxides with hydrogen will generate unwanted water which needs to be removed to meet product specifications. Therefore, there is a need for an improved method for removing oxygen from oxygen containing hydrogen gas streams without generation of water.